Conveyor systems

ABSTRACT

A power-and-free conveyor system has a load trolley track formed of two parallel, spaced channel-form parts opening towards each other. Load trolleys running in the track each include two vertical side plates readily releasably interconnected by horizontal nut-and-bolt or pin-and-circlip connections. Each plate carries two rollers rolling in the track about horizontal axes and one roller rolling in the track about a vertical axis, the latter roller extending into a recess in the other plate. To remove each trolley from the track, the connections are released, dogs and certain other members removed, the plates are moved in opposite directions along the track so that the one roller of each plate leaves the associated recess, and each plate and its rollers are removed as a unit from the track in generally a width direction of the two channels.

United States Patent Turner Aug. 20, 1974 CONVEYOR SYSTEMS 3,195,474 7/1965 Dehne 105 155 Inventor: J h e S e e ge E g and 3,348,496 10/1967 Klamp et al. 104/94 [73] Assignee: Geo. W. King Limited, Stevenage, Primary Examiner-Drayton E. Hoffman England Attorney, Agent, or Firm-Waters, Roditi, Schwartz & 221 Filed: Jan. 4, 1973 [21] App]. No: 320,939 [57] ABSTRACT I A power-and-free conveyor system has a load trolley Foreign Application p Data tracik formed tof tw) parztilllei,h spalceddctharlilnel-form par s openmg owar s eac 0 er. 0a r0 eys run- Oct. 11, 1972 Great Bntam 46976/72 g in the track each include two vertical Side plates readily releasably interconnected by horizontal nut- [52] us Cl 104/172 104/94 3 5 and-bolt or pin-and-circlip connections. Each plate 51 1111.01. Bg 17/42, B61b 3/00 carries 3 f l *2; axes an one ro er r0 1ng1n e rac a ou aver 1ca [58] Flew of Search 104/94 g g, axis, the latter roller extending into a recess in the other plate. To remove each trolley from the track, [56] References Cited the connections are released, dogs and certain other members removed, the plates are moved in opposite UNITED STATES PATENTS directions along the track so that the one roller of 2,485,215 10/1949 Rose /155 each plate leaves the associated recess, and each plate Czarnecki and its rollers are removed as a unit from the track in 3,049,083 8/1962 Potter et al. 104/94 generally a width direction of the two channels 3,076,418 2/1963 Orwm 104/94 3,086,482 4/1963 Fiegel et a1. 105/155 2 Claims, 8 Drawing Figures u-lil co W 4 BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a trolley of a conveyor system, particularly a power-and-free conveyor system, and to methods of removing the trolley from a track of the system and of mounting the trolley in the track.

2. Description of the Prior Art In a known power-and-free conveyor system, load trolleys are driven along a load trolley track by pushers depending from a power chain attached to chain trolleys running in a chain track extending parallel to and above the load trolley track. Each track consists of two channel-form parts which extend parallel to each other along the track and the mouths of which open towards each other and are spaced from each other. Each load trolley includes two vertical side plates which are spaced from and parallel to each other. Arranged between the plates of each load trolley are driving and holdback dogs of each trolley, while arranged laterally outside the plates are front and rear pairs of guide wheels whereby the trolley is guided in the load trolley track and which rotate about horizontal axes. Each driving dog is linearly displaceable perpendicularly to the tracks by means of a proximity lever projecting forwards from the trolley, while each holdback dog is pivotable relative to the plates. The linear displacement of each driving dog is guided by guide rollers between the side plates. The latter are fixed to each other by rivetting at the pivot axes of the holdback dog and the proximity lever and at the rolling axes of the guide rollers. Each trolley is also guided in the track by front and rear single guide wheels which rotate about axes perpendicular to the tracks and which run in the gap between the respective lower flanges of the channel-form parts of the load trolley track. The two single guide wheels of each trolley are both mounted on one of the two side plates of the trolley and extend into recesses formed in the other of the side plates, th ese recesses extending parallelly to the load trolley track from the respective front and rear edges of that other side plate.

This known arrangement is found to be particularly disadvantageous when the load trolley is damaged or breaks down and thus needs to be taken out of service. It is often necessary to move the trolley some considerable distance along its track to a maintenance section of the track. Depending on the damage to or failure in the trolley, it may have to be moved through this distance by hand. Thus the time that the conveyor is out of operation may be quite considerable, taking into account for example the need to move all of the preceding or following trolleys out of the way. So a whole production line may be put out of operation for a considerable time with an appreciable resulting loss of production, simply because of damage to or failure of a single trolley. Even when the trolley has been forwarded to the maintenance section, the rivets have to be drilled out before the trolley can be dismantled to be repaired. They cannot all be drilled out at the damage or breakdown region and then the trolley be dismantled at that region, because the channel-form parts of the load trolley track prevent access to the rivets by a drill. Moreover, even if it were possible to drill out all of the rivets at the damage or breakdown region, the trolley still could not be dismantled at that region because the aforementioned other side plate .is restrained in its movement relative to the aforementioned one side plate by the'two single guide wheels which extend in the recesses in that other side plate.

SUMMARY OF THE INVENTION According to one aspect of the present invention, there is provided in a conveyor system, a combination comprising a track comprised of first and second channel-form parts which extend parallel to each other along the track and the mouths of which open towards each other and are spaced from each other, and a trolley carried by said track and comprising first and second frame members, first and second guide wheels disposed in the track to roll in the respective channel-form parts and mounted on the respective frame members, and connecting means readily releasably interconnecting said first andsecond frame members, each of the frame members and its associated wheel, following release of said connecting means, being removable from said track, with the wheel still mounted on the frame member, in generally a direction of the width dimension of said mouths.

According to another aspect of the present invention, there is provided a method of removing a trolley from a track in a conveyor system, which track is comprised of first and second channel-form parts whichextend parallel to each other along the track and the mouths of which open towards each other and are spaced from each other, comprising releasing readily releasable connecting means which interconnect first and second frame members of said trolley on which are mounted respective first and second guide wheels disposed in the track to roll in the respective channel-form parts, and subsequently removing each of the frame members and its associated wheel from said track, with the wheel still mounted on the frame member, in generally a direction of the width dimension of said mouths.

According to a further aspect of the present invention, there is provided a method of mounting a trolley in a track in a conveyor system, which track is comprised of first and second channel-form parts which extend parallel to ach other along the track and the mouths of which open towards each other and are spaced from each other, comprising inserting a first trolley frame member mounting a first guide wheel to between said channel-form parts in generally a direction of the width dimension of said mouths, inserting a second trolley frame member mounting a second guide wheel to between said channel-form parts in generally a direction of said width dimension, and then interconnecting the first frame member and the second frame member with readily releasable connecting means so that the first and second guide wheels are disposed to roll in the respective channel-form parts.

By means of the invention, it is possible for a damaged or failed load trolley to be dismantled and removed from the track at or near the damage or breakdown location on the load trolley track, and also, if desired, forthe repaired trolley or a replacement trolley,

to be assembled in the'track at or near the damage or breakdown location. Thus loss of production can be appreciably reduced.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be clearly understood and readily carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

FIG. 1 is a diagrammatic, fragmentary, perspective view of part of a conveyor system,

FIG. 2 shows a rear elevation of a load-carrying trolley of the system, a track being shown in cross-section,

FIG. 3 shows a section through the trolley taken substantially on the line Ill-Ill of FIG. 2,

FIG. 4 shows a plan view of a sub-assembly of the trolley,

FIG. 5 shows a side elevation of the sub-assembly, but with two wheels removed for the sake of clarity,

FIG. 6 shows a rear end view of that sub-assembly,

FIG. 7 shows a side elevation of another subassembly of the trolley, and

FIG. 8 shows a rear end view of that other subassembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, the conveyor system is of the power-and-free kind, in which identical loadcarrying trolleys (of which one is shown and referenced 10) supporting load-suspension bars (of which one is shown and referenced 11) are propelled along a load carrying trolley track 12 by a chain 13 mounted by identical chain trolleys (of which one is shown and referenced 14) in a chain trolley track 16. The trolley 14 carries a pusher dog 17 which co-operates with a reciprocable driving dog 18 and a pivotal hold-back dog 19 carried at the top of the trolley 10 to advance the trolley 10 along the track 12 and to hold back the trolley 10, respectively.

Each track 12 or 16 is comprised of two channelform parts which extend parallel to each other along the track and the mouths of which open towards each other and are spaced from each other. The two .channel-form parts of the track 12 are referenced 20 in FIG. 2. The trolley 10 includes a pair of front wheels 21 and a pair of rear wheels 22,'each pair of wheels rotating about a common horizontal axis. The wheels 21 roll in the respective parts 20 and bear on the lower flanges of the respective parts 20, the wheels 22 doing likewise. The trolley l0 also has a forward single wheel 23 and a rearward single wheel 24, each of which rolls in the gap between inner edges 41 of the flanges 25 and rotates about an axis perpendicular to the plane of the horizontal axes of the wheels 21 and 22. The trolley has a form of frame which consists of two vertical, lateral, co-extensive plates 26 and 27 interconnected at a spacing from each other by two horizontal nut, bolt and collar devices 28 and 36. The plate 26 has fixed thereto bearings 29, 30, and 31 whereby are mounted on the plate 26, the wheels 21 and 22 at the same side of the trolley as the plate 26, as well as the wheel 24. Similarly, the plate 27 has fixed thereto bearings 29 to 31 for the wheels 21 and 22 at the other side of the trolley, as well as the wheel 23. The forward wheel 23 extends through recesses 42 and 43 formed in the plates 26 and 27, respectively, and extending rearwardly from the forward edges of those plates, while the rearward wheel 24 extends through recesses 44 and 45 formed in the plates 26 and 27, respectively and extending forwardly from the rearward edges of those plates. Thus, each plate extends through the space between the wheels 23 and 24.

The driving dog 18 is mountedbetween the plates 26 and 27 and is guided by rollers 32 so as to be reciprocable perpendicularly to the plane containing the axes of the wheels 21 and 22, the lower end of the dog 18 being formed with a horizontal recess 33 along which slides a pin 34 fixed in one end of a two-arm proximity lever 35 pivotally mounted on the device 36. Clockwise movement of the lever 35 is limited by a horizontal pin 46. The dog 18 is roughly or T-shape with its cross limb extending lengthwise of the track 12. The rear end 37 of its cross limb co-operates with a forward portion of the dog 19 such that, when the dog 18 is lowered, the dog 19 is lowered simultaneously. The dog 19 is turnable about a horizontal pivot 38. Mounted on the respective plates 26 and 27 are limit-switch strikers 39 which serve to operate limit switches (not shown). All of the transverse pins or bolts which extend through the plates 26 and 27 are retained therein by some readily releasable means such a circlips or nuts. For example, the pivot 38 is retained by circlips 40. To remove the trolley 10 from the track 12, for example in the case of breakdown of the trolley, initially the device 36 is released and removed and the lever 35 removed forwardly. With the dog 18 no longer retained by the pin 34, the dog 18 can now be removed vertically upwardly. Next the circlips 40 are detached and the pivot 38 withdrawn, so that the dog 19 can be removed. Then the remaining readily releasable means are released and removed. There now remains in the track the two sub-assemblies of FIGS. 4 and 7. One of these is displaced along the track 12 relatively to the other in a direction such that the wheel 23 or 24 moves out of the open end of the recess 42 or 45 and until the one subassembly is free of the other and its lower end is then turned outwardly so that the plate of the sub-assembly becomes oblique to the vertical. This turning swings the wheel 23 or 24 downwardly out of the gap between the flanges 25. Thereupon, by further manipulation the plate 26 or 27 and the wheels 21 and 22 mounted thereon can be removed downwardly through that gap. The other sub-assembly is then removed in a similar manner. It will be appreciated that such removal of each of the sub-assemblies takes place in generally a direction of the width dimension of the mouths of the parts 20.

It will be readily appreciated that mounting of the trolley in the track 12 can be performed in a reverse manner to the removal thereof from the track, so that the operation of mounting the trolley in the track need not be described in detail.

The present invention is applicable to various kinds of trolleys, for example to leading rolleys, intermediate trolleys, or trailing trolleys, of load carriers of a powerand-free conveyor system, or to load carriers formed by respective single trolleys.

A principle advantage of the trolley described with reference to the drawings is that the user can rapidly replace the trolley in the event of a breakdown, thus minimizing the lost production time, particularly since there is no need to divert the affected trolley to the maintenance section of the conveyor system, which could be at a considerable distance away from the breakdown.

I claim:

1. In a conveyor system a combination comprising a track having first and second channel-form parts extending parallel to each other along the track, said parts having mouths which open towards each other and are spaced from each other, and a trolley carried by said track and comprising first and second frame members, first and second guide wheels disposed in the track to roll in the respective channel-form parts and mounted on the respective frame members, and connecting means releasably interconnecting said first and second frame members, each of the frame members with associated wheel following release of said connecting means, being removable from said track, with the wheel remaining mounted on the frame member, in v substantially longitudinal direction of said track. 

1. In a conveyor system a combination comprising a track having first and second channel-form parts extending parallel to each other along the track, said parts having mouths which open towards each other and are spaced from each other, and a trolley carried by said track and comprising first and second frame members, first and second guide wheels disposed in the track to roll in the respective channel-form parts and mounted on the respective frame members, and connecting means releasably interconnecting said first and second frame members, each of the frame members with associated wheel following release of said connecting means, being removable from said track, with the wheel remaining mounted on the frame member, in substantially a direction of the width dimension of said mouths, said trolley further comprising a lever pivotally mounted between said frame members on a releasable connection of said connecting means, a driving dog slidingly guided between said frame members by said frame members and other releasable connections of said connecting means, and a releasable coupling between said lever and said driving dog whereby said lever can displace said dog.
 2. A combination according to claim 1, wherein said releasable coupling comprisEs a pin-and-slot coupling, having a pin which can be withdrawn from the slot in substantially longitudinal direction of said track. 